Electrical spring contact probes are inserted into receptacles which are in turn inserted into a test fixture and connected by individual wires to a test logic device. The test fixture is then typically brought into engagement with a printed circuit board through a vacuum mechanism. Once in contact, computer generated test routines are routed through the wires and the probes to the printed circuit board to determine continuity and identify failure of the board circuit traces. With miniaturization of electronic circuits, the circuit tracings in the printed circuit board have become closer, and with the miniaturization of integrated circuit chips, chip footpads have become even more densely packed. This densely packed array of footpads and test sites for the electrical spring contact probes is commonly as low as 0.050 inches center to center.
The receptacles into which the spring probes are placed are each connected to an insulated, flexible wire. Normally, the wires are crimped or soldered to the receptacles; however, several techniques for using replaceable or reusable terminations have existed. Two such arrangements are shown in connection with U.S. Pat. Nos. 4,720,275 to Everett/Charles Contact Products, Inc. and 4,597,622 to QA Technology Company. Both of these companies are competitors to the assignee, and these two patents disclose termination arrangements which were heretofore the state of the art. Wire terminations on close centers, such as 0.050 inch centers, present a major challenge to the automated test equipment (ATE) industry. In addition to the terminations shown in the '275 and '622 patents, some wire to probe connections have been made by wire-wrapping, but wrapping on such fine pitch (e.g., closely-spaced) probes is difficult and normally requires special fixtures. Other methods, such as crimping and soldering, are too slow to be cost efficient with the volume of terminals which must be connected. The ATE industry has recently been using preattached wires as an alternative, but this method has disadvantages as well. Replacing or reassigning wires normally requires removal of the receptacle, and prewiring the receptacle to the fixture interface is difficult, if not impossible.